The present invention relates to a sheathed-element glow plug for auto-igniting internal combustion engines. Known sheathed-element glow plugs generally consist of a sheath, a connection terminal for the glow current, a tube secured to the sheath, the tube being sealed at the end facing away from the sheath, and a wire-filament-shaped resistor element which is embedded in thermally conductive insulating powder. The resistor element is arranged in the part of the tube which functions as the glow pencil and which protrudes out of the sheath. Sheaths for the various commercially available sheathed-element glow plugs vary depending on the structural shape and type of construction of the engine into which the sheathed-element glow plug is to be installed. Sheaths also differ in their length, which determines the overall length of the sheathed-element glow plugs. Therefore, for manufacturing purposes, sheaths and connection terminals for contacting the heating element must be available in great variety and in varying lengths.